Each time your heart beats, it pumps blood to carry oxygen and nutrients to all parts of your body. Your heart’s pumping action makes pressure waves that push blood through your arteries – your blood vessels taking blood away from the heart. Blood pressure is the force of the pressure wave pushing against the walls of your arteries. It is related to the amount of blood flow (how strong and fast your heart is pumping) and the resistance to pushing blood through your arteries.
This is similar to a garden hose, where the pressure of the water flowing through the hose is related to the amount of flow coming out of the tap and the resistance of the nozzle at the end of the hose. More flow and more resistance makes a higher pressure. The top of the pressure wave in our arteries is called the systolic blood pressure and the bottom of the pressure wave is called the diastolic blood pressure.
Our blood pressure changes through the day and from day to day to adjust to our activity and surroundings. Normally it is lowest when we are resting and changes with our activity and even our emotions. These temporary changes are completely normal. It is only when the blood pressure remains high that hypertension has developed. This can happen to anyone but it becomes much more common as we get older and starts earlier if one or both of our parents also have high blood pressure.
When someone has hypertension, the constantly elevated blood pressure will cause damage to their blood vessels and the organs that they supply blood to. This can cause strokes, heart attack, heart and kidney failure, dementia and erectile dysfunction. Finding high blood pressure before the blood vessels and organs are damaged and lowering it to normal with lifestyle changes and medications if necessary lowers the risk of developing these problems.